1 // Copyright 2012 Google Inc. All Rights Reserved. 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // http://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 15 #ifndef POLO_ENCODING_SECRETENCODER_H_ 16 #define POLO_ENCODING_SECRETENCODER_H_ 17 18 #include <stdint.h> 19 #include <string> 20 #include <vector> 21 22 namespace polo { 23 namespace encoding { 24 25 // Encodes and decodes secret challenges. The decoded secret is displayed to the 26 // user on the display device, and entered by the user on the input device. The 27 // secret is encoded for transmission on the wire and used for computing pairing 28 // keys. 29 class SecretEncoder { 30 public: 31 virtual ~SecretEncoder() {} 32 33 // Encodes a byte array representation of a secret to a string. 34 // @param secret the secret bytes 35 // @return a string representation of the given secret 36 virtual std::string EncodeToString( 37 const std::vector<uint8_t>& secret) const = 0; 38 39 // Decodes the string representation of the secret to a byte array. 40 // @param secret a string representation of the secret 41 // @return the decoded secret as a byte array 42 virtual std::vector<uint8_t> DecodeToBytes( 43 const std::string& secret) const = 0; 44 45 // The number of symbols contained in each byte of data. For example, a 46 // hexadecimal encoding has 4 bytes per symbol and therefore 2 symbols per 47 // byte. 48 virtual size_t symbols_per_byte() const = 0; 49 }; 50 51 } // namespace encoding 52 } // namespace polo 53 54 #endif // POLO_ENCODING_SECRETENCODER_H_ 55
